Moravian instruments, Inc., source:, printed: 17.8.2017 7:55:16

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8-positions XS external filter wheel for G2 cameras
 The smallest XS variant of the external filter wheel for G2 cameras offers 7 positions for unmounted D36 mm filters. Because filters are further from the sensor in the case of external filter wheel compared to internal filter wheel, greater filter diameter allows usage of the G2-8300 camera with largest sensor within G2 series to be used with fast optics without vignetting. But other models of the G2 series contain smaller sensors and they can work D31 mm filters. A possibility to build a new variant of the XS external filter wheel for D31 mm filters occurred. Smaller filter diameter allows increasing of the number of filter positions from 7 to 8, despite the external filter wheel dimensions remain unchanged..

Outer dimensions of the XS external filter wheel are the same, only the wheel itself holding filters contains 8 positions for unmounted D31 mm filers or filters in standard 1.25" threaded cells (the same filters can be used in the G2 camera internal filter wheels, containing just 5 positions).

G2 camera head with XS filter wheel attached

It is not recommended to combine the external filter wheel with D31 mm filters with G2-8300 camera. While the limiting focal ratio is f/2.2 if D36 mm filters are used (which is well within margins of almost any optics available), the limiting non-vignetting focal ratio is only f/4.7 if D31 mm filters are used.

Filter wheels with 7 and 8 positions for EFW-SX


Camera system driver version 2.1 or higher must be used to control filter wheel with 8 positions. If the system driver is installed from USB Flash Drive supplied with the camera of from newly downloaded installation package, compatibility with a new filter wheel is ensured. But if the camera with EFW-XS8 is connected to a computer, where some older driver with lower version is already installed, the camera would work well, but the filter wheel will not be recognized.

If the camera is controlled drought the Gx Camera Ethernet Adapter, it is necessary to make sure the adapter firmware is of version 27 or higher.